Impregnated Grades
In addition to virgin PTFE products, BTR offers a wide range of compounded products as well.
Among these compounds, which are manufactured from selected polymers and special high-purity fillers, end users are able to find the right answer to their requirements of application.
The following table shows the way each filler affects physical and mechanical properties.
Combinations of two or more fillers (not considered in the table) allow a large number of compounds. Thus the resulting combined properties offer a variety of applications.
PTFE impregnated grades filler affects
Filler
|
Property
|
Most common applications
|
Glass |
- Enhanced wear resistance.
- Enhanced chemical resistance (except for alkali and hydrofluoric acid).
|
- Valve seats, seals, bearings, requested to resist sliding and chemicals.
- Suitable for bearings working at low PV values.
|
Graphite |
- Extremely low coefficient of friction.
- Fairly good compressive strength.
- Good wear resistance.
|
- Bearings for high speed on fairly hard surface.
|
Carbon |
- Good thermal conductivity.
- Good resistance to deformation.
|
- Valve seats.
- Bearings for high speed and when fast dissipation of electric charges is needed.
- Elastic bands for non-lubricated compressors.
|
Molybdenum disulphide |
- Enhanced non-stick properties.
- Low static coefficient of friction.
- Fairly good resistance to deformation.
|
- Guide bands.
- Details needing good resistivity.
|
Bronze |
- Enhanced compressive strength.
- Good wear resistance and high thermal conductivity.
|
- Anti-extrusion rings.
- Non-lubricated bearings for high speed on not hard surface.
|
Table: shows PTFE impregnated grades filler affects
Properties - 25% Carbon Impregnated
Property |
Unit of measure |
Value |
Tensile Strength |
Mpa |
15-20 |
Elongation at Break |
% |
150-200 |
Modulus of Elasticity |
MPa |
- |
Impact Strength |
kj/m² |
- |
Compressive Strength |
MPa |
7-9 |
Shear Strength |
MPa |
- |
Shore Hardness |
D Scale |
60-65 |
Co-efficient of Friction |
μ |
0.13 |
Water Absorption @ 23 Deg C |
% |
0.03 |
Service Temperature Intermittent |
ᵒC |
310 |
Service Temperature Continuous |
ᵒC |
260 |
Melting point |
ᵒC |
335 |
Thermal Conductivity |
W/m.ᵒC |
0.54 |
Dielectric Strength |
kV/mm |
2 |
Volume Resistivity |
Ω.cm |
10⁴ |
Surface Resistivity |
Ω |
10⁷ |
Arc Resistance |
Sec |
- |
Properties - 25% Glass Impregnated
Property |
Unit of measure |
Value |
Tensile Strength |
Mpa |
14-21 |
Elongation at Break |
% |
230-270 |
Modulus of Elasticity |
MPa |
3100 |
Impact Strength |
kj/m² |
8.5 |
Compressive Strength |
MPa |
8-9 |
Shear Strength |
MPa |
- |
Shore Hardness |
D Scale |
62-67 |
Co-efficient of Friction |
μ |
0.13 |
Water Absorption @ 23 Deg C |
% |
0.02 |
Service Temperature Intermittent |
ᵒC |
310 |
Service Temperature Continuous |
ᵒC |
260 |
Melting point |
ᵒC |
335 |
Thermal Conductivity |
W/m.ᵒC |
0.46 |
Dielectric Strength |
kV/mm |
13 |
Volume Resistivity |
Ω.cm |
10¹⁵ |
Surface Resistivity |
Ω |
10¹⁶ |
Arc Resistance |
Sec |
- |
Properties - 60% Bronze Impregnated
Property |
Unit of measure |
Value |
Tensile Strength |
Mpa |
17-23 |
Elongation at Break |
% |
100-160 |
Modulus of Elasticity |
MPa |
- |
Impact Strength |
kj/m² |
- |
Compressive Strength |
MPa |
10-11 |
Shear Strength |
MPa |
- |
Shore Hardness |
D Scale |
65-70 |
Co-efficient of Friction |
μ |
0.13 |
Water Absorption @ 23 Deg C |
% |
0.05 |
Service Temperature Intermittent |
ᵒC |
310 |
Service Temperature Continuous |
ᵒC |
260 |
Melting point |
ᵒC |
335 |
Thermal Conductivity |
W/m.ᵒC |
0.77 |
Dielectric Strength |
kV/mm |
0 |
Volume Resistivity |
Ω.cm |
10⁷ |
Surface Resistivity |
Ω |
10⁹ |
Arc Resistance |
Sec |
- |
Properties - 15% Graphite Impregnated
Property |
Unit of measure |
Value |
Tensile Strength |
Mpa |
15-20 |
Elongation at Break |
% |
170-250 |
Modulus of Elasticity |
MPa |
- |
Impact Strength |
kj/m² |
- |
Compressive Strength |
MPa |
6.5-7.5 |
Shear Strength |
MPa |
- |
Shore Hardness |
D Scale |
55-60 |
Co-efficient of Friction |
μ |
0.07 |
Water Absorption @ 23 Deg C |
% |
0.03 |
Service Temperature Intermittent |
ᵒC |
310 |
Service Temperature Continuous |
ᵒC |
260 |
Melting point |
ᵒC |
335 |
Thermal Conductivity |
W/m.ᵒC |
0.52 |
Dielectric Strength |
kV/mm |
2 |
Volume Resistivity |
Ω.cm |
10⁴ |
Surface Resistivity |
Ω |
10⁷ |
Arc Resistance |
Sec |
- |